Today, the digital watermarking technique is used for a content copy right protection/management system, content related service providing system and the like.
For the purpose of content identification/management, copyright protection/management, providing related information and the like when distributing content such as image, video and voice, there are methods using the digital watermark embedding technique for embedding other information into the content such that it is not perceived.
For example, there is a using method for inputting a still image such as printed material with a camera so as to obtain related information by detecting digital watermark from the input image (refer to non-patent document 1, for example).
In addition, there is a method for continuously performing camera input and digital watermark detection in real time to improve detection performance (refer to non-patent document 2, for example).
[Non-patent document 1] Nakamura, Katayama, Miyaji, Yamashita, Yamamuro, “Digital watermark detection scheme for service mediation using camera-equipped mobile-phone”, Forum on Information Technology, FIT2003, N-020, September, 2003.
[Non-patent document 2] Nakamura, Miyatake, Hayashi, Katayama, Yamamuro, “Real time digital watermark detection scheme from camera input image”, Forum on Information Technology, FIT2004, J-036, September, 2004.